Certain industrial automation controllers and other electronics modules utilize a high-speed microprocessor (processor) and other electronic components that generate heat beyond that which can be dissipated sufficiently using natural convection airflow. In such cases, the controller must utilize a fan to flow forced air through the controller housing in which the processor is located to cool the processor.
Use of a fan to cool an industrial automation controller has drawbacks including fan reliability in that fan failure can lead to overheating and failure, throttling (slowing), or shut-down of the controller. As such, in a fan-cooled industrial automation controller or other electronic system, fan monitoring and control is essential to provide a warning of impending fan failure and to optimize fan operation in case one or more fans fail or begins to degrade in performance.
Known systems have not provided a suitable arrangement for removing a replacing a fan in a “hot-swapping” (Removal and Insertion Under Power (RIUP)) process in which the fan is removed and replaced without interrupting the operation of the industrial automation controller. Hot-swapping of a fan or other device presents challenges that must be addressed to prevent damage to the system in which devices are being removed and replaced to ensure continued operation of the system and long term reliability. In some cases, the system does not have sufficient time to prepare for removal of the device being removed and replaced which can lead to inability of the system to adjust for the removal of the device. This can lead to unexpected system responses which are highly undesirable.
An important goal is to maximize the product life of an industrial automation or other electronics controller module. As such, it is desirable to keep the temperature of the processor and/or other electronics parts of the controller as close as possible to an optimal temperature at which the processor is not thermally stressed. While this could be achieved by running a fan at full speed all the time, this would result in shorter fan life, increased power consumption and increased noise, so this is not an optimal solution.
As such, a need has been identified for an industrial automation controller system and method with fan monitoring and control to provide a warning of impending fan failure and to optimize fan operation in case one or more fans fail or begins to degrade in performance. A need has also been identified for such a system in which a fan can be removed and replaced in a hot-swapping operation that is tightly controlled to prevent undesired system responses. A need has also been found for a new and improved fan control solution achieves the required cooling while maximizing fan life, reducing power consumption and noise, and that facilitates repair and replacement of a fan when required without a shutdown of the controller module.